Some of my guildies are trying to get their FR cranked up and noticed something about max.Resist. Set pieces that have a set bonus of "+8 to All Resistances" are not factored in, even when those pieces COULD be worn with the items it does correctly find.

For example:

Trella is a rogue in our guild wearing at least two pieces of the Darkmantle set, getting the +8 to all resistances. The max.Resist addon locates addition gear he could swap in that wouldn't remove those two items, so the +8 would still apply. Yet the +8 isn't included.

Not sure how easy this one is to overcome, but wanted to raise it to your attention. Otherwise, guildies have had no complaints and love it! (Well, a few get confused by the Soulbound bit, but I set 'em straight.)